This section provides a reference of all configuration parameters that can be used with Nominatim.

Configuring Nominatim

Nominatim uses dotenv to manage its configuration settings. There are two means to set configuration variables: through an .env configuration file or through an environment variable.

The .env configuration file needs to be placed into the project directory. It must contain configuration parameters in <parameter>=<value> format. Please refer to the dotenv documentation for details.

The configuration options may also be set in the form of shell environment variables. This is particularly useful, when you want to temporarily change a configuration option. For example, to force the replication serve to download the next change, you can temporarily disable the update interval:

NOMINATIM_REPLICATION_UPDATE_INTERVAL=0 nominatim replication --once

If a configuration option is defined through .env file and environment variable, then the latter takes precedence.

Configuration Parameter Reference

Import and Database Settings

NOMINATIM_DATABASE_DSN

Summary
Description: Database connection string
Format: string: pgsql:<param1>=<value1>;<param2>=<value2>;...
Default: pgsql:dbname=nominatim
After Changes: run nominatim refresh --website

Sets the connection parameters for the Nominatim database. At a minimum the name of the database (dbname) is required. You can set any additional parameter that is understood by libpq. See the Postgres documentation for a full list.

Note

It is usually recommended not to set the password directly in this configuration parameter. Use a password file instead.

NOMINATIM_DATABASE_WEBUSER

Summary
Description: Database query user
Format: string
Default: www-data
After Changes: cannot be changed after import

Defines the name of the database user that will run search queries. Usually this is the user under which the webserver is executed. When running Nominatim via php-fpm, you can also define a separate query user. The Postgres user needs to be set up before starting the import.

Nominatim grants minimal rights to this user to all tables that are needed for running geocoding queries.

NOMINATIM_DATABASE_MODULE_PATH

Summary
Description: Directory where to find the PostgreSQL server module
Format: path
Default: empty (use <project_directory>/module)
After Changes: run nominatim refresh --functions
Comment: Legacy tokenizer only

Defines the directory in which the PostgreSQL server module nominatim.so is stored. The directory and module must be accessible by the PostgreSQL server.

For information on how to use this setting when working with external databases, see Advanced Installations.

The option is only used by the Legacy tokenizer and ignored otherwise.

NOMINATIM_TOKENIZER

Summary
Description: Tokenizer used for normalizing and parsing queries and names
Format: string
Default: legacy
After Changes: cannot be changed after import

Sets the tokenizer type to use for the import. For more information on available tokenizers and how they are configured, see Tokenizers.

NOMINATIM_TOKENIZER_CONFIG

Summary
Description: Configuration file for the tokenizer
Format: path
Default: empty (default file depends on tokenizer)
After Changes: see documentation for each tokenizer

Points to the file with additional configuration for the tokenizer. See the Tokenizer descriptions for details on the file format.

If a relative path is given, then the file is searched first relative to the project directory and then in the global settings directory.

NOMINATIM_MAX_WORD_FREQUENCY

Summary
Description: Number of occurrences before a word is considered frequent
Format: int
Default: 50000
After Changes: cannot be changed after import
Comment: Legacy tokenizer only

The word frequency count is used by the Legacy tokenizer to automatically identify stop words. Any partial term that occurs more often then what is defined in this setting, is effectively ignored during search.

NOMINATIM_LIMIT_REINDEXING

Summary
Description: Avoid invalidating large areas
Format: bool
Default: yes

Nominatim computes the address of each place at indexing time. This has the advantage to make search faster but also means that more objects needs to be invalidated when the data changes. For example, changing the name of the state of Florida would require recomputing every single address point in the state to make the new name searchable in conjunction with addresses.

Setting this option to 'yes' means that Nominatim skips reindexing of contained objects when the area becomes too large.

NOMINATIM_LANGUAGES

Summary
Description: Restrict search languages
Format: string: comma-separated list of language codes
Default: empty

Normally Nominatim will include all language variants of name:XX in the search index. Set this to a comma separated list of language codes, to restrict import to a subset of languages.

Currently only affects the initial import of country names and special phrases.

NOMINATIM_TERM_NORMALIZATION

Summary
Description: Rules for normalizing terms for comparisons
Format: string: semicolon-separated list of ICU rules
Default: :: NFD (); [[:Nonspacing Mark:][:Cf:]] >; :: lower (); [[:Punctuation:][:Space:]]+ > ' '; :: NFC ();
Comment: Legacy tokenizer only

Special phrases have stricter matching requirements than normal search terms. They must appear exactly in the query after this term normalization has been applied.

Only has an effect on the Legacy tokenizer. For the ICU tokenizer the rules defined in the normalization section will be used.

NOMINATIM_USE_US_TIGER_DATA

Summary
Description: Enable searching for Tiger house number data
Format: boolean
Default: no
After Changes: run nominatim refresh --functions

When this setting is enabled, search and reverse queries also take data from Tiger house number data into account.

NOMINATIM_USE_AUX_LOCATION_DATA

Summary
Description: Enable searching in external house number tables
Format: boolean
Default: no
After Changes: run nominatim refresh --functions
Comment: Do not use.

When this setting is enabled, search queries also take data from external house number tables into account.

Warning: This feature is currently unmaintained and should not be used.

NOMINATIM_HTTP_PROXY

Summary
Description: Use HTTP proxy when downloading data
Format: boolean
Default: no

When this setting is enabled and at least NOMINATIM_HTTP_PROXY_HOST and NOMINATIM_HTTP_PROXY_PORT are set, the configured proxy will be used, when downloading external data like replication diffs.

NOMINATIM_HTTP_PROXY_HOST

Summary
Description: Host name of the proxy to use
Format: string
Default: empty

When NOMINATIM_HTTP_PROXY is enabled, this setting configures the proxy host name.

NOMINATIM_HTTP_PROXY_PORT

Summary
Description: Port number of the proxy to use
Format: integer
Default: 3128

When NOMINATIM_HTTP_PROXY is enabled, this setting configures the port number to use with the proxy.

NOMINATIM_HTTP_PROXY_LOGIN

Summary
Description: Username for proxies that require login
Format: string
Default: empty

When NOMINATIM_HTTP_PROXY is enabled, use this setting to define the username for proxies that require a login.

NOMINATIM_HTTP_PROXY_PASSWORD

Summary
Description: Password for proxies that require login
Format: string
Default: empty

When NOMINATIM_HTTP_PROXY is enabled, use this setting to define the password for proxies that require a login.

NOMINATIM_OSM2PGSQL_BINARY

Summary
Description: Location of the osm2pgsql binary
Format: path
Default: empty (use binary shipped with Nominatim)
Comment: EXPERT ONLY

Nominatim uses osm2pgsql to load the OSM data initially into the database. Nominatim comes bundled with a version of osm2pgsql that is guaranteed to be compatible. Use this setting to use a different binary instead. You should do this only when you know exactly what you are doing. If the osm2pgsql version is not compatible, then the result is undefined.

NOMINATIM_WIKIPEDIA_DATA_PATH

Summary
Description: Directory with the wikipedia importance data
Format: path
Default: empty (project directory)

Set a custom location for the wikipedia ranking file. When unset, Nominatim expects the data to be saved in the project directory.

NOMINATIM_ADDRESS_LEVEL_CONFIG

Summary
Description: Configuration file for rank assignments
Format: path
Default: address-levels.json

The address level configuration defines the rank assignments for places. See Place Ranking for a detailed explanation what rank assignments are and what the configuration file must look like.

When a relative path is given, then the file is searched first relative to the project directory and then in the global settings directory.

NOMINATIM_IMPORT_STYLE

Summary
Description: Configuration to use for the initial OSM data import
Format: string or path
Default: extratags

The style configuration describes which OSM objects and tags are taken into consideration for the search database. Nominatim comes with a set of pre-configured styles, that may be configured here.

You can also write your own custom style and point the setting to the file with the style. When a relative path is given, then the style file is searched first relative to the project directory and then in the global settings directory.

See Import Styles for more information on the available internal styles and the format of the configuration file.

NOMINATIM_FLATNODE_FILE

Summary
Description: Location of osm2pgsql flatnode file
Format: path
Default: empty (do not use a flatnote file)
After Changes: Only change when moving the file physically.

The osm2pgsql flatnode file is file that efficiently stores geographic location for OSM nodes. For larger imports it can significantly speed up the import. When this option is unset, then osm2pgsql uses a PsotgreSQL table to store the locations.

When a relative path is given, then the flatnode file is created/searched relative to the project directory.

Warning

The flatnode file is not only used during the initial import but also when adding new data with nominatim add-data or nominatim replication. Make sure you keep the flatnode file around and this setting unmodified, if you plan to add more data or run regular updates.

NOMINATIM_TABLESPACE_*

Summary
Description: Group of settings for distributing the database over tablespaces
Format: string
Default: empty (do not use a table space)
After Changes: no effect after initial import

Nominatim allows to distribute the search database over up to 10 different PostgreSQL tablespaces. If you use this option, make sure that the tablespaces exist before starting the import.

The available tablespace groups are:

NOMINATIM_TABLESPACE_SEARCH_DATA
Data used by the geocoding frontend.
NOMINATIM_TABLESPACE_SEARCH_INDEX
Indexes used by the geocoding frontend.
NOMINATIM_TABLESPACE_OSM_DATA
Raw OSM data cache used for import and updates.
NOMINATIM_TABLESPACE_OSM_DATA
Indexes on the raw OSM data cache.
NOMINATIM_TABLESPACE_PLACE_DATA
Data table with the pre-filtered but still unprocessed OSM data. Used only during imports and updates.
NOMINATIM_TABLESPACE_PLACE_INDEX
Indexes on raw data table. Used only during imports and updates.
NOMINATIM_TABLESPACE_ADDRESS_DATA
Data tables used for computing search terms and addresses of places during import and updates.
NOMINATIM_TABLESPACE_ADDRESS_INDEX
Indexes on the data tables for search term and address computation. Used only for import and updates.
NOMINATIM_TABLESPACE_AUX_DATA
Auxiliary data tables for non-OSM data, e.g. for Tiger house number data.
NOMINATIM_TABLESPACE_AUX_INDEX
Indexes on auxiliary data tables.

Replication Update Settings

NOMINATIM_REPLICATION_URL

Summary
Description: Base URL of the replication service
Format: url
Default: https://planet.openstreetmap.org/replication/minute
After Changes: run nominatim replication --init

Replication services deliver updates to OSM data. Use this setting to choose which replication service to use. See Updates for more information on how to set up regular updates.

NOMINATIM_REPLICATION_MAX_DIFF

Summary
Description: Maximum amount of data to download per update cycle (in MB)
Format: integer
Default: 50
After Changes: restart the replication process

At each update cycle Nominatim downloads diffs until either no more diffs are available on the server (i.e. the database is up-to-date) or the limit given in this setting is exceeded. Nominatim guarantees to downloads at least one diff, if one is available, no matter how small the setting.

The default for this setting is fairly conservative because Nominatim keeps all data downloaded in one cycle in RAM. Using large values in a production server may interfere badly with the search frontend because it evicts data from RAM that is needed for speedy answers to incoming requests. It is usually a better idea to keep this setting lower and run multiple update cycles to catch up with updates.

When catching up in non-production mode, for example after the initial import, the setting can easily be changed temporarily on the command line:

NOMINATIM_REPLICATION_MAX_DIFF=3000 nominatim replication

NOMINATIM_REPLICATION_UPDATE_INTERVAL

Summary
Description: Publication interval of the replication service (in seconds)
Format: integer
Default: 75
After Changes: restart the replication process

This setting determines when Nominatim will attempt to download again a new update. The time is computed from the publication date of the last diff downloaded. Setting this to a slightly higher value than the actual publication interval avoids unnecessary rechecks.

NOMINATIM_REPLICATION_RECHECK_INTERVAL

Summary
Description: Wait time to recheck for a pending update (in seconds)
Format: integer
Default: 60
After Changes: restart the replication process

When replication updates are run in continuous mode (using nominatim replication), this setting determines how long Nominatim waits until it looks for updates again when updates were not available on the server.

Note that this is different from NOMINATIM_REPLICATION_UPDATE_INTERVAL. Nominatim will never attempt to query for new updates for UPDATE_INTERVAL seconds after the current database date. Only after the update interval has passed it asks for new data. If then no new data is found, it waits for RECHECK_INTERVAL seconds before it attempts again.

API Settings

NOMINATIM_CORS_NOACCESSCONTROL

Summary
Description: Send permissive CORS access headers
Format: boolean
Default: yes
After Changes: run nominatim refresh --website

When this setting is enabled, API HTTP responses include the HTTP CORS headers access-control-allow-origin: * and access-control-allow-methods: OPTIONS,GET.

NOMINATIM_MAPICON_URL

Summary
Description: URL prefix for static icon images
Format: url
Default: empty
After Changes: run nominatim refresh --website

When a mapicon URL is configured, then Nominatim includes an additional icon field in the responses, pointing to an appropriate icon for the place type.

Map icons used to be included in Nominatim itself but now have moved to the nominatim-ui project. If you want the URL to be included in API responses, make the /mapicon directory of the project available under a public URL and point this setting to the directory.

NOMINATIM_DEFAULT_LANGUAGE

Summary
Description: Language of responses when no language is requested
Format: language code
Default: empty (use the local language of the feature)
After Changes: run nominatim refresh --website

Nominatim localizes the place names in responses when the corresponding translation is available. Users can request a custom language setting through the HTTP accept-languages header or through the explicit parameter accept-languages. If neither is given, it falls back to this setting. If the setting is also empty, then the local languages (in OSM: the name tag without any language suffix) is used.

NOMINATIM_SEARCH_BATCH_MODE

Summary
Description: Enable a special batch query mode
Format: boolean
Default: no
After Changes: run nominatim refresh --website

This feature is currently undocumented and potentially broken.

NOMINATIM_SEARCH_NAME_ONLY_THRESHOLD

Summary
Description: Threshold for switching the search index lookup strategy
Format: integer
Default: 500
After Changes: run nominatim refresh --website

This setting defines the threshold over which a name is no longer considered as rare. When searching for places with rare names, only the name is used for place lookups. Otherwise the name and any address information is used.

This setting only has an effect after nominatim refresh --word-counts has been called to compute the word frequencies.

NOMINATIM_LOOKUP_MAX_COUNT

Summary
Description: Maximum number of OSM ids accepted by /lookup
Format: integer
Default: 50
After Changes: run nominatim refresh --website

The /lookup point accepts list of ids to look up address details for. This setting restricts the number of places a user may look up with a single request.

NOMINATIM_POLYGON_OUTPUT_MAX_TYPES

Summary
Description: Number of different geometry formats that may be returned
Format: integer
Default: 1
After Changes: run nominatim refresh --website

Nominatim supports returning full geometries of places. The geometries may be requested in different formats with one of the polygon_* parameters. Use this setting to restrict the number of geometry types that may be requested with a single query.

Setting this parameter to 0 disables polygon output completely.

Logging Settings

NOMINATIM_LOG_DB

Summary
Description: Log requests into the database
Format: boolean
Default: no
After Changes: run nominatim refresh --website

Enable logging requests into a database table with this setting. The logs can be found in the table new_query_log.

When using this logging method, it is advisable to set up a job that regularly clears out old logging information. Nominatim will not do that on its own.

Can be used as the same time as NOMINATIM_LOG_FILE.

NOMINATIM_LOG_FILE

Summary
Description: Log requests into a file
Format: path
Default: empty (logging disabled)
After Changes: run nominatim refresh --website

Enable logging of requests into a file with this setting by setting the log file where to log to. A relative file name is assumed to be relative to the project directory.

The entries in the log file have the following format:

<request time> <execution time in s> <number of results> <type> "<query string>"

Request time is the time when the request was started. The execution time is given in ms and corresponds to the time the query took executing in PHP. type contains the name of the endpoint used.

Can be used as the same time as NOMINATIM_LOG_DB.